"""
Author: Uyanide pywang0608@foxmail.com
Date: 2026-03-25 02:33:26
Description: Base fetcher class and common interfaces.
"""

from abc import ABC, abstractmethod
from typing import Optional
from dataclasses import dataclass

from ..models import CacheStatus, TrackMeta, LyricResult


@dataclass(frozen=True, slots=True)
class FetchResult:
    synced: Optional[LyricResult] = None
    unsynced: Optional[LyricResult] = None

    @staticmethod
    def from_not_found() -> "FetchResult":
        return FetchResult(
            synced=LyricResult(status=CacheStatus.NOT_FOUND, lyrics=None, source=None),
            unsynced=LyricResult(
                status=CacheStatus.NOT_FOUND, lyrics=None, source=None
            ),
        )

    @staticmethod
    def from_network_error() -> "FetchResult":
        return FetchResult(
            synced=LyricResult(
                status=CacheStatus.NETWORK_ERROR, lyrics=None, source=None
            ),
            unsynced=LyricResult(
                status=CacheStatus.NETWORK_ERROR, lyrics=None, source=None
            ),
        )


class BaseFetcher(ABC):
    @property
    @abstractmethod
    def source_name(self) -> str:
        """Name of the fetcher source."""
        pass

    @property
    def self_cached(self) -> bool:
        """True if this fetcher manages its own cache (skip per-source cache check)."""
        return False

    @abstractmethod
    def is_available(self, track: TrackMeta) -> bool:
        """Check if the fetcher is available for the given track (e.g. has required metadata)."""
        pass

    @abstractmethod
    async def fetch(self, track: TrackMeta, bypass_cache: bool = False) -> FetchResult:
        """Fetch lyrics for the given track. Returns None if unable to fetch."""
        pass